Gas Nitriding Services
Nitriding is the process of saturating the surface of the steel with nitrogen. Saturation is accomplished in an atmosphere of ammonia gas (NH3) at temperatures ranging 480°C (896°F) to 580°C (1076°F). Ammonia dissociate to nascent nitrogen and hydrogen when in contact with the hot jobs 2NH3®2N + 3H2. Atomic nitrogen formed diffuses into alpha iron and saturate the metal. Nitrided steel acquire high hardness and retain the hardness even after subsequent heating to 600°C (1112°F). Nitriding increases wear resistance, fatigue and corrosion resistance. Nitriding is usually applied to medium carbon and alloy steels containing carbon and alloy steels containing aluminium, chromine, molybdenum and other elements that are capable of forming nitrides since the process is done at lower temperature, the time cycle will be longer than the caburising cycle. It is preferable to harden and temper the parts prior to nitriding to achieve best properties. The tempering temperature should be minimum of 20°C (68°F) to 30°C (86°F) more thus the nitriding temperature to retain the core properties. The nitrided depth usually between 0.2mm to 0.4mm. No quenching is required as high hardness is obtained directly after this process